Saturday, August 18, 2012

THE RACE: What the "Runner's High" Could Say About Our Pre-disposition to Run

I'm very proud to say that I've never done any illegal drugs...The only mind-altering substance I've put into my system is alcohol, and that's even pretty infrequent nowadays.  So yes, for me, there were no crazy stoner college days (well, there were crazy days, but not drug-related), no experimentation, no late-night snack cravings (well, at least no drug-induced snack cravings).  

So maybe that's why I have yet to ever experience - in my 14 years of running - that much talked about "runner's high."  My body just doesn't know how to actually "get high."  For me, it's elusive...For scientists it's also a fairly elusive concept...

What is the "runner's high?"

On a basic level, it's believed that endorphins released during exercise are responsible for elevated moods.  But until 2008, there was no science to back up that hypothesis.

The 2008 German study.  

In 2008, German researchers conducted a brain imaging study that actually showed, for the first time, the increase of endorphins in certain areas of the runner's brain during a two-hour jogging session.  They used positron emission tomography ("PET") to scan the brains of ten runners before and after their running session.

The result:  verification of the body's production of its own opioids (endorphins) during long-distance running.  To measure the endorphin release, the researchers used a radioactive substance that normally binds with the brain's opiate receptors; however, that substance will not bind with those receptors if endorphins are present to compete and bind to the receptors instead.  The study showed that during the two-hour run, there was significantly less binding of the radioactive substance, which meant that endorphins were being released to bind with those receptors instead.

The affected regions of the brain were the prefrontal and limbic regions, which play a key role in emotional processing.  The runners also reported increased happiness and euphoria as a result of the run.  Researchers found that the more intensely the high was experienced, the more the endorphins were being released (i.e., the less the radioactive substance was binding with the opiate receptors).

Three lessons from the research.

There are three important lessons to take from this:

  1. Endorphins released during long-distance running could function as a "pain-killer" for your body.  Scientists know that endorphins help with the body's pain suppression by influencing the way the body processes pain; however, more research is needed to corroborate this precise connection.  But this could help explain why so many runners can just tough it out through pain during a run.   
  2. The results also are relevant for those who suffer from chronic pain because of the body's release of its own opiates to suppress pain. 
  3. There could be a relation between genetic disposition and opiate receptor distribution in the brain.  As one of the German researchers stated, it's possible that "we ran because our genes wanted us to do so."  
It's this last possibility that actually intrigues me the most.  Think about that:  our genes may be telling us to run.  If you haven't read Born to Run by Chris McDougall, you must do so immediately.  Never has a book so fueled my deep-seeded desire not only to run, but to do so in the more natural state/form that our bodies were designed to perform.  (I'll set aside the whole mid-foot vs. heel-strike debate for now, but let's just say I'm an advocate of the mid-foot strike).  To oversimplify the theme of McDougall's book:  our bodies were made to run.  He talks in several places about our ancestral running roots and how, in the beginning, we ran for survival:
“Distance running was revered because it was indispensable; it was the way we survived and thrived and spread across the planet. You ran to eat and to avoid being eaten; you ran to find a mate and impress her, and with her you ran off to start a new life together. You had to love running, or you wouldn't live to love anything else. And like everything else we love-everything we sentimentally call our 'passions' and 'desires'-it's really an encoded ancestral necessity. We were born to run; we were born because we run.”    
When you think about that - the fact that our bodies are designed to run and that we've done so from Day #1 in the human timeline - the role of genetics in running seems so common-sense, and particularly in the endorphin-induced "runner's high."  

The "addiction" of running.

To take this to a bit of an extreme, we've all heard that genetics may play a role in addictions.  Some studies even conclude that as much as 50-60% of addiction is due to genetics.  Of course, other factors such as stress, environment, lifestyle, etc. also play a significant role, so genetics are not, by any means, determinative.  But focusing on the genetic aspect for just a moment, it's not a huge leap to conclude that not only are we genetically predisposed to be able to run, but also, in at least some small part, potentially predisposed to experience the endorphin-induced "high" we can get from running.

Does that mean everyone can run, that every runner experiences the "runner's high," or that every runner is "addicted" (in the strictest sense) to running?  Absolutely not.  Just because my parents may or may not have been runners or athletes, doesn't determine 100% whether I'm going to be a good runner or athlete.  The training, environment, personality type, etc., are all factors.  But my ancestral pre-disposition to be influenced by the soothing feelings created by an endorphin release quite possibly is a factor in my enjoyment of running and, thus, in my ability to run better or worse.

To be sure, some people can be addicted to running, cycling, or other intense activities in ways that are similar to other addictions.  The soothing feeling some people get from opiates or morphine, is the same as the soothing feeling a runner gets from the endorphin release.  Thus, some people can become literally addicted to exercise.  They experience the "high" from intense exercise and gradually come to rely on that high to create pleasure, much in the same way an alcoholic could come to rely on having drinks to ease their pain.  Afterall, don't we all, to some extent, use exercise as an escape from our problems - to experience a period of time where we can feel that euphoria that lifts us away from the other stressors in our lives?

Well, there's a point where that's certainly healthy - otherwise, doctors wouldn't recommend exercise as a way to relieve stress and lead a healthier life.  But there's also a point where it can become unhealthy if the runner or athlete takes it to an extreme. Individuals who are addicted to intense exercise come to depend on it in unhealthy ways.  They experience the short-lived euphoria from exercise, and then come to need that euphoria more and more frequently, leading them to exercise more intensely or often.  They may even start to slip away from family and friends.  At that point, the person needs help just as any addict would.

The Bottom Line...

Not everyone experiences the "runner's high" to the same extent and some people may not even experience it all.  Certainly I usually feel much better after a workout because of my elevated endorphin levels.  But I've never had that "out-of-body experience" that some people have when they run.  And there could be a lot of factors, including genetics, that explain that.  Likewise, while it's possible that we humans literally are "born to run," we're not all made to run at the same level.  Our training, personalities, lifestyle, and other factors all influence our running abilities.  By the same token, all of those factors can influence whether we can maintain our exercise habits in a healthy manner, or take them to an extreme unhealthy level.  Bottom line:  try to observe how you feel before and after exercise, and make sure your exercise habits continue to take you down a healthy path where exercise is only one of many ways that you can experience natural euphoria in your life.

Have you experienced the "runner's high?"  Have there been times (that you're willing to admit) where you may have taken your exercise to an unhealthy level?     




1 comment:

Jen said...

I have never taken exercise to an unhealthy level, but I do think that there are times when I probably rely on it a bit too much. I can get particularly antsy over a missed run. I have learned that the forced month off I recently experienced was a good thing (in retrospect) because it gave me a chance to see where I was veering off into a bad path - focusing on ever increasing mileage and never taking cutbacks because I couldn't bear not to post a bigger number than last week on my spreadsheet, not cross-training, etc. Classic buildup to overuse and thus, an overuse injury had to be dealt with. This was a great post, something to rattle around in my head a little, thanks!